1. Field of the Invention
The present invention relates to a machining machine system which determines acceptance/rejection of workpieces.
2. Description of the Related Art
In manufacturing factories, by a machining machine, such as a machine tool, an injection molding machine, or a robot for arc welding, etc., machining and welding an object to be machined (workpiece), etc., are performed. Further, to machine a workpiece, machining machines constitute a manufacturing line, such as a manufacturing cell. In such a case, each machining machine which constitutes the manufacturing cell is controlled by a cell controller via a communication network. The cell controller is managed by a higher-order host controller.
In such a machining machine system, a determination of acceptance/rejection of a workpiece as machined by the machining machines is performed by an inspection with respect to the total number of workpieces or by a sampling inspection.
For example, as disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2006-146459, known is a semiconductor device manufacturing system in which from history data of device log information, abnormality determination threshold values are created, and an abnormality determination of wafer machining processing is performed.
Further, for example, as disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2002-341909, known is a method for a workpiece machining device in which sampling points are set in an operation process, and using a standard deviation of a signal at each of the points, the presence/absence of an abnormality in the operation process is monitored.
Still further, for example, as disclosed in Japanese Unexamined Patent Publication (Kokai) No. 2010-76177, known is an acceptance/rejection determination device which measures a physical quantity of a pressure, a speed, a time, etc., that influence a molded product quality, and sets an upper limit value and a lower limit value to perform an acceptance/rejection determination of a molded product.
When the acceptance/rejection determination of a workpiece as machined by the machining machines is performed with respect to the total number of workpieces, inspection accuracy increases, whereas a large number of steps are necessary and efficiency is poor. On the other hand, when the sampling inspection is performed instead of the total inspection, the number of workpieces which are targets of the acceptance/rejection determination can be reduced, whereas rejects may not be detected.